Medicine:Ulnar neuropathy

Ulnar neuropathy
Nerves of the left upper extremity. (Ulnar labeled at center)
Symptoms	Numbness(fingers)
Causes	Nerve entrapment, Tumor
Diagnostic method	CBC, Urinalysis
Treatment	NSAIDs, Surgery

Ulnar neuropathy is a disorder involving the ulnar nerve. Ulnar neuropathy may be caused by entrapment of the ulnar nerve with resultant numbness and tingling. It may also cause weakness or paralysis of the muscles supplied by the nerve.

Signs and symptoms

In terms of the signs/symptoms of ulnar neuropathy trauma and pressure to the arm and wrist, especially the elbow, the medial side of the wrist, and other sites close to the course of the ulnar nerve are of interest in this condition. Many people complain of sensory changes in the fourth and fifth digits. Rarely, an individual actually notices that the unusual sensations are mainly in the medial side of the ring finger (fourth digit). Sometimes the third digit is also involved, especially on the ulnar (medial) side. The sensory changes can be a feeling of numbness or a tingling, pain rarely occurs in the hand. Complaints of pain tend to be more common in the arm, up to and including the elbow area, which is probably the most common site of pain in an ulnar neuropathy.

Causes

Among the causes of ulnar neuropathy are the following-

Olecranon

Much more commonly, ulnar neuropathy is caused by overuse of the triceps muscle and repetitive stress combined with poor ergonomics. Overused and hypertonic triceps muscle causes inflammation in the tendon and adhesions with the connective tissue surrounding that tendon and muscle. These in turn impinge on or trap the ulnar nerve. Ulnar neuropathy resulting from repetitive stress is amenable to massage and can usually be fully reversed without cortisone or surgery. Center for Occupational and Environmental Neurology, Baltimore, MD has this to say: “Repetitive Strain Injuries (RSI) refers to many different diagnoses of the neck/shoulder, arm, and wrist/hand area usually associated with work-related ergonomic stressors. Other terms used for Repetitive Strain Injuries are overuse syndrome, musculoskeletal disorders, and cumulative trauma disorders. Some of the more common conditions under these headings include: Cubital Tunnel Syndrome-compression of the ulnar nerve in the cubital tunnel at the elbow.”

Pathophysiology

In regards to the pathophysiology of ulnar neuropathy:the axon, and myelin can be affected. Within the axon, fascicles to individual muscles could be involved, with subsequent motor unit loss and amplitude decrease. Conduction block means impaired transmission via a part of the nerve. Conduction block can mean myelin damage to the involved area, slowing of conduction or significant spreading out of the temporal profile of the response with axonal integrity is a hallmark of demyelination.

Diagnosis

Nerve conduction study (Calculation of NCV)

Among the diagnostic procedures done to determine if the individual has ulnar neuropathy are (but may not be limited to the following):

• Nerve conduction exam/study (Nerve Conduction Velocity is a measurements made in a nerve conduction exam)
• Physical exam
• Medical history
• X-ray
• CBC
• Urinalysis
• MRI
• Ultrasound
• Histology study

Ulnar nerve neuropathy at the elbow or the wrist can be assessed by testing for a positive Froment's sign. Little finger abduction and adduction can be tested as well.

Treatment

Treatment for ulnar neuropathy can entail: NSAID (non-steroidal anti-inflammatory) medicines. there is also the option of a cortisone injection. Another possible option is splinting, to secure the elbow, a conservative procedure endorsed by some. In cases where surgery is needed, cubital tunnel release, where the ligament of the cubital tunnel is cut, thereby alleviating pressure on nerve can be performed.

Treatment for the common occurrence of ulnar neuropathy resulting from overuse, with no fractures or structural abnormalities, is treatment massage, ice, and anti-inflammatories. Specifically, deep tissue massage to the triceps, myofascial release for the upper arm connective tissue, and cross-fiber friction to the triceps tendon.

Prognosis

In terms of the prognosis of ulnar neuropathy early decompression of the nerve sees a return to normal ability (function), which should be immediate. Severe cubital tunnel syndrome tends to have a faster recovery process in individuals below the age of 70, as opposed to those above such an age. Finally, revisional surgery for cubital tunnel syndrome does not result well for those individuals over 50 years of age.

Further reading

• "NIOSHTIC-2 Publications Search - 20045060 - Do comorbid ulnar symptoms or ulnar neuropathy affect the prognosis of workers with carpal tunnel syndrome?". https://www.cdc.gov/niosh/nioshtic-2/20045060.html. 
• Yoon, Joon Shik; Walker, Francis O.; Cartwright, Michael S. (1 February 2010). "Ulnar Neuropathy With Normal Electrodiagnosis and Abnormal Nerve Ultrasound". Archives of Physical Medicine and Rehabilitation 91 (2): 318–320. doi:10.1016/j.apmr.2009.10.010. ISSN 0003-9993. PMID 20159139. 
• Warner, Mark A.; Warner, David O.; Matsumoto, Joseph Y.; Harper, Michel C.; Schroeder, Darrell R.; Maxson, Pamela M. (1 January 1999). "Ulnar Neuropathy in Surgical Patients". The Journal of the American Society of Anesthesiologists 90 (1): 54–59. doi:10.1097/00000542-199901000-00009. ISSN 0003-3022. PMID 9915312. http://anesthesiology.pubs.asahq.org/article.aspx?articleid=1947443. Retrieved 23 July 2016. 

External links

Classification	D ICD-10: G56.2 ICD-9-CM: 354.2
External resources	eMedicine: article/1141515